Optical tape embosser drum with shim identification

ABSTRACT

A method is provided for making an embossing drum that is useable to emboss tape media. The method includes assembling together multiple stamper plates that each have embossing features for embossing tape media, and the stamper plates include at least one first plate and at least one second plate. Furthermore, the embossing features of each first plate are inverted with respect to the embossing features of each second plate.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No. 14/329,105filed Jul. 11, 2014, the disclosure of which is hereby incorporated inits entirety by reference herein.

TECHNICAL FIELD

The disclosure relates to an embosser drum for tape media, and tomethods of making an embosser drum and components thereof.

BACKGROUND

Roll-to-roll nano-imprinting lithography systems, such as platform 10shown in FIG. 1, have been proposed as an efficient and effective meansof pre-formatting optical tape media with imprint of nanometerdimensional structure (nano-structure features or patterns) such aswobbled edge groove track patterns (referred to as “wobble patterns”).These systems typically involve several operational stages, such asshown with platform 10 of FIG. 1. The platform 10 also includes a tapetransport system 12 for moving an optical tape media 14 through thedifferent stages, which may include coating and sputtering stages 16, 18for coating the media 14 with an appropriate embossing monomer and otherchemicals, an embossing stage 20 for imprinting the desired pattern onthe media 14, a curing stage 22 for curing the embossed media 14 and aslitting stage 24 for cutting the media 14. The platform shown in FIG. 1also includes a tension sensor 26 that is in communication with thetransport system 12 to provide information regarding the tension of themedia 14.

The function of the embossing stage 20 is to imprint the nano-structurepatterns into the media 14 using an embossing drum 28 that has thepatterns formed in its hard surface. By the process of pressing the drum28 into the monomer coating on the media 14 and subsequent curing of themonomer material, the patterns may be imprinted into the media 14 withnano-dimensional accuracy and fidelity.

The development of the embossing drum 28 will now be discussed withreference to FIG. 2. The development process starts first with thedesign of nano-structure features or patterns and their layout, as shownin box 30, followed by formation of a quartz or silicon “master” 32 thatis etched with the nano-structure patterns. Identical inverse replicasof the patterns of the master 32 are then made by producing multiplerigid polymer-material replicas 34 of the master 32. Next, thin metalshims or stamper plates 36 with the nano-structure patterns are formedby electroplating surfaces of the replicas 34. The thin metal plates 36are then processed and formed to make segments of the embossing drum 28.The segments are welded together at seams to create the final embossingdrum 28 such that the embossing drum 28 contains four identical stampersplates 36.

SUMMARY

According to one aspect of the present disclosure, a method of makingstamper plates for an embossing drum that is useable to emboss tapemedia is provided. The method includes forming one or more first stamperplates using a master template, and forming a second stamper plate fromone of the one or more first stamper plates such that the second stamperplate and the one first stamper plate have inverse land and groovepatterns. Furthermore, the second stamper plate and the one firststamper plate or another of the one or more first stamper plates areuseable on the drum to emboss tape media.

According to another aspect of the present disclosure, a method ofmaking an embossing drum that is useable to emboss tape media isprovided. The method includes assembling together multiple stamperplates that each have embossing features for embossing tape media, andthe stamper plates include at least one first plate and at least onesecond plate. Furthermore, the embossing features of each first plateare inverted with respect to the embossing features of each secondplate.

According to yet another aspect of the present disclosure, an embossingdrum for embossing tape media is provided. The embossing drum includes afirst stamper plate for embossing the tape media, and a second stamperplate positioned proximate the first stamper plate for embossing thetape media, wherein the stamper plates have inverse land and groovepatterns.

While exemplary embodiments are illustrated and disclosed, suchdisclosure should not be construed to limit the claims. It isanticipated that various modifications and alternative designs may bemade without departing from the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a roll-to-roll nano-imprint lithographysystem including an embossing drum for imprinting optical tape media;

FIG. 2 is a schematic view showing details of a manufacturing processfor making the embossing drum shown in FIG. 1;

FIG. 3 is a schematic view showing details of a manufacturing processfor making an embossing drum according to the present disclosure;

FIG. 4 is a schematic view showing additional details of themanufacturing process for making the embossing drum of FIG. 3;

FIG. 5 is a plan view of a first stamper shim or plate of the embossingdrum of FIG. 3;

FIG. 6 is a plan view of a second stamper shim or plate of the embossingdrum of FIG. 3;

FIG. 7 is a plan view of first and second portions of tape media thathave been imprinted by the first and second stamper plates,respectively; and

FIG. 8 is a plan view showing four stamper plates welded together formaking the embossing drum shown in FIG. 3.

DETAILED DESCRIPTION

Embodiments of the present disclosure are described herein. It is to beunderstood, however, that the disclosed embodiments are merely examplesand that other embodiments can take various and alternative forms. Thefigures are not necessarily to scale; some features could be exaggeratedor minimized to show details of particular components. Therefore,specific structural and functional details disclosed herein are not tobe interpreted as limiting, but merely as a representative basis forteaching one skilled in the art to variously employ the presentinvention. As those of ordinary skill in the art will understand,various features illustrated and described with reference to any one ofthe figures can be combined with features illustrated in one or moreother figures to produce embodiments that are not explicitly illustratedor described. The combinations of features illustrated providerepresentative embodiments for typical applications. Variouscombinations and modifications of the features consistent with theteachings of this disclosure, however, could be desired for particularapplications or implementations.

FIG. 3 shows an embosser or embossing drum 110, according to the presentdisclosure, which may be used to emboss optical tape media. For example,the embossing drum 110 may be used in the system or platform 10 shown inFIG. 1 in place of the embossing drum 28 to emboss the media 14. Theembossing drum 110, however, provides an innovative way to identifyshims or stamper plates 112 used to make the drum 110.

The embossing drum 110 may include one or more first stamper plates 112a for embossing the tape media, and one or more second stamper plates112 b positioned proximate the one or more first stamper plates 112 afor also embossing the tape media. In the embodiment shown in FIG. 3,the embossing drum 110 includes two first stamper plates 112 a and twosecond stamper plates 112 b that have nanometer dimensional structure(nano-structure features or patterns) formed thereon, such that thestamper plates 112 a and 112 b can be distinguished from each other asexplained below in further detail. The nano-structure features mayinclude embossing features 113, such as land and groove patterns thatdefine wobbled edge groove track patterns, which may be referred to as“wobble patterns.”

Each first plate 112 a may be formed using a single master template 114,such as a quartz or silicon master. For example, one or more replicas116, such as polymer replicas, may be formed from the master template114, and each first stamper plate 112 a may be formed from one of thereplicas 116 such as by electroplating nickel or other suitable materialonto one of the replicas 116, and then removing the thus formed firststamper plate 112 a from the replica 116. As another example, each firststamper plate 112 a may be formed from the same replica 116.Furthermore, referring to FIGS. 3 and 4, the second stamper plates 112 bmay each be formed from one of the first stamper plates 112 a that isused with the drum 110, or each second stamper plate 112 b may be formedfrom another first stamper plate 112 a made from one of the replicas116, or both second stamper plates 112 b may be formed from the samefirst stamper plate 112 a (either a first stamper plate 112 a that isused with the drum 110 or another first stamper plate 112 a). Forexample, each second stamper plate 112 b may be formed by electroplatingnickel or other suitable material onto a first stamper plate 112 a, andthen removing the thus formed second stamper plate 112 b from the firststamper plate 112 a. Because each second stamper plate 112 b is madefrom a first stamper plate 112 a, the first stamper plates 112 a may bereferred to as “mother” plates or shims, and the second stamper plates112 b may be referred to as “son” plates or shims.

With the above manufacturing process, all of the stamper plates 112 a,112 b may be formed using a single master template 114. Furthermore,since each second stamper plate 112 b is formed from a first stamperplate 112 a, the embossing features of each second plate 112 b areinverted with respect to the embossing features of each first plate 112a. For example, each land 113 a on a first stamper plate 112 acorresponds to a groove 113 b formed on a second stamper plate 112 b,and each groove on a first stamper plate 112 a corresponds to a landformed on a second stamper plate 112 b. In addition, the embossingfeatures 113 b of each second plate 112 b may also be verticallymirrored (e.g., longitudinally mirrored in a direction of tape mediatravel) with respect to the embossing features 113 a of each first plate112 a, as shown schematically in FIG. 4.

Referring to FIG. 5, an exemplary first stamper plate 112 a is shown inmore detail. In the illustrated embodiment, the first stamper plate 112a is divided into first, second, third and fourth sections 118 a, 120 a,122 a and 124 a, respectively. The first section 118 a may be apost-seam field or section (e.g., a section to be located after a seamby or at which the first stamper plate 112 a is connected to anotherstamper plate), the fourth section may be a pre-seam field or section(e.g., a section to be located prior to a seam by or at which the firststamper plate 112 a is connected to another stamper plate), and thesecond and third sections 120 a and 122 a may be located between thefirst and fourth sections 118 a and 124 a and on opposite sides of acenterline 126 a of the first stamper plate 112 a. Furthermore, thesecond section 120 a may be referred to as an address field, and thethird section 122 a may be referred to as a reversed address field. Acorresponding direction of travel 127 for tape media to be imprinted bythe first stamper plate 112 a is also shown in FIG. 5.

In the embodiment shown in FIG. 5, the first and fourth sections 118 aand 124 a are horizontally mirrored (e.g., laterally mirrored) withrespect to each other. Furthermore, the first section 118 a has groovepatterns with identically wobbled edges 128 a, for example, and thefourth section 124 a has land patterns with identically wobbled edges130 a.

Referring to FIG. 6, an exemplary second stamper plate 112 b is shown inmore detail. As mentioned above, because the second stamper plate 112 bis formed from a first stamper plate 112 a, the first and second stamperplates 112 a and 112 b have inverse land and groove patterns. Forexample, land patterns in the first stamper plate 112 a become orcorrespond to groove patterns in the second stamper plate 112 b, andgroove patterns in the first stamper plate 112 a become or correspond toland patterns in the second stamper plate 112 b.

Furthermore, the second stamper plate 112 b is divided into first,second, third and fourth sections 118 b, 120 b, 122 b and 124 b,respectively, and the second stamper plate 112 b is vertically mirroredwith respect to the first stamper plate 112 a. Therefore, the first,second, third and fourth sections 118 b, 120 b, 122 b and 124 b,respectively, of the second stamper plate 112 b are respectively relatedor correspond to the fourth, third, second and first sections 124 a, 122a, 120 a and 118 a, respectively, of the first stamper plate 112 a. Inaddition, in the embodiment shown in FIGS. 5 and 6, the first section118 b of the second stamper plate 112 b is a horizontal mirror replicaof the first section 118 a of the first stamper plate 112 a, and thefourth section 124 b of the second stamper plate 112 b is a horizontalmirror replica of the fourth section 124 a of the first stamper plate112 a.

The stamper plates 112 a and 112 b may be assembled together in anysuitable manner to form the drum 110. For example, referring to FIG. 3,the stamper plates 112 a and 112b may be bent or otherwise formed into acurved configuration and welded or connected together in any suitablemanner at seams 132 to form a cylindrical body. That cylindrical bodymay then be placed over an expandable hub that can be expanded (e.g.,mechanically expanded) to engage the cylindrical body. With such aconfiguration, the cylindrical stamper plate body may be removed fromthe hub and replaced with a different cylindrical stamper plate body asneeded.

The stamper plates 112 a and 112 b may also be oriented in any suitablemanner so that the stamper plates 112 a and 112 b may be distinguishedfrom each other based on imprints on the tape media made by the stamperplates 112 a and 112 b. In that regard, a tape drive in which the tapemedia is received may include a suitable optical reader or detector 133(shown in FIG. 7), such as a wobble address decoder or index matchedfilter, that may read or otherwise detect information, such as anidentifier, at the beginning and end of each imprinted portion of thetape media corresponding to the beginning and end, respectively, of aparticular stamper plate 112 a, 112 b, and output a suitable signal orsignals corresponding to the detected information. For example, thedetector 133 may detect the shape of an index pulse or pulse identifierin a pre/post field of the imprinted tape media, and output a positiveor a negative pulse signal (or a signal corresponding to a “1” or a “0”identifier, respectively) depending on the shape of the detected indexpulse. That information may then be used to determine which stamperplate 112 a, 112 b was used to imprint the particular section of tapemedia.

Referring to FIG. 7, for example, a first portion 134 a of tape mediaimprinted by one of the first stamper plates 112 a is shown at the topportion of that Figure, and a second portion 134 b of tape mediaimprinted by one of the second stamper plates 112 b is shown at thebottom portion of that Figure. Each tape portion 134 a, 134 b is dividedinto tape sections that are identified with the same referenceidentifiers used to identify the corresponding stamper plate sectionsthat were used to emboss the tape sections, except the referenceidentifiers for the tape sections each include a prime mark.Furthermore, the section orientation for each tape portion is verticallymirrored with respect to the corresponding stamper plate. For example,the rightmost section of the first tape media portion 134 a isidentified with reference identifier 118 a′, and the leftmost section ofthe first tape media portion 134 a is identified with referenceidentifier 124 a′. In the embodiment shown in FIG. 7, the rightmostsection 118 a′, which corresponds to a post-seam field, defines a “high”or “positive” index pulse or pulse identifier, and the leftmost section124 a′, which corresponds to a pre-seam field, defines a “low” or“negative” index pulse or pulse identifier. Likewise, the rightmostsection 118 b′ (which corresponds to a post-seam field) of the secondtape media portion 134 b′ defines a “low” or “negative” index pulse orpulse identifier, and the leftmost section 124 b′ (which corresponds toa pre-seam field) of the second tape media portion 134 b′ defines a“high” or “positive” index pulse or pulse identifier.

With the above configuration, two first stamper plates 112 a and twosecond stamper plates 112 b may be oriented in any suitable manner, suchas shown in FIG. 8, so that the corresponding index pulses imprintedonto the tape media will enable identification of each particularstamper plate. In the embodiment shown in FIG. 8, for example, thestamper plates 112 a, 112 b are arranged in the following order: secondstamper plate 112 b (shim 1)—second stamper plate 112 b (shim 2)—firststamper plate 112 a (shim 3)—first stamper plate 112 a (shim 4). Thecorresponding index pulse polarity associated with each end of eachstamper plate 112 a, 112 b is also shown in FIG. 8.

That same index pulse polarity is imprinted onto the tape media duringthe embossing procedure. The index pulse polarity detected by thedetector 133 in the drive during use of the tape media may then be usedto determine which particular stamper plate 112 a, 112 b was used toimprint a particular portion of the tape media. For example, based ondetected index pulse polarity or pulse identifiers at tape medialocations corresponding to post- and pre-seam fields of the stamperplates, the particular stamper plate may be identified using thefollowing table:

Detected Index Pulse Polarity Assigned Shim/Stamper Plate Identifier L-LBeginning of shim/stamper plate 1 H-L Beginning of shim/stamper plate 2H-H Beginning of shim/stamper plate 3 L-H Beginning of shim/stamperplate 4

With the above arrangement, the embossing drum 110 havingdistinguishable or identifiable stamper plates or shims may beefficiently made using a single master template. Stamper plate or shimidentification may be important for longitudinal addressing of the tapemedia, for example. Furthermore, with the above arrangement, portions ofthe imprinted tape media may be accurately correlated with particularsections of the embossing drum 110. As a result, defective stamperplates may be readily identified and/or formation of improved stamperplates for future use may be enabled.

An embossing drum according to the present disclosure may include anysuitable number of stamper plates that may be formed using a singlemaster template. For example, depending on desired size of a particularembossing drum, two or more stamper plates may be used to form theembossing drum. In one embodiment, an embossing drum according to thedisclosure may be provided with eight stamper plates including four ofthe above described first stamper plates 112 a and four second stamperplates 112 b that are arranged in the following order, for example:second stamper plate 112 b (shim 1)—second stamper plate 112 b (shim2)—first stamper plate 112 a (shim 3)—first stamper plate 112 a (shim4)—second stamper plate 112 b (shim 5)—second stamper plate 112 b (shim6)—first stamper plate 112 a (shim 7)—first stamper plate 112 a (shim8). Based on detected index pulse polarity or pulse identifiers at tapemedia locations corresponding to post- and pre-seam fields of thestamper plates, the stamper plates may be identified using the followingtable, for example:

Detected Index Pulse Polarity Assigned Shim/Stamper Plate Identifier L-LBeginning of shim/stamper plate 1 H-L Beginning of shim/stamper plate 2H-H Beginning of shim/stamper plate 3 L-H Beginning of shim/stamperplate 4 L-L Beginning of shim/stamper plate 5 H-L Beginning ofshim/stamper plate 6 H-H Beginning of shim/stamper plate 7 L-H Beginningof shim/stamper plate 8

While exemplary embodiments are described above, it is not intended thatthese embodiments describe all possible forms of the invention. Rather,the words used in the specification are words of description rather thanlimitation, and it is understood that various changes may be madewithout departing from the spirit and scope of the invention.Additionally, the features of various implementing embodiments may becombined to form further embodiments of the invention.

What is claimed is:
 1. A method of making an embossing drum that isuseable to emboss tape media, the method comprising: assembling togethermultiple stamper plates that each have embossing features for embossingtape media, the stamper plates including at least one first plate and atleast one second plate, wherein the embossing features of each firstplate are inverted with respect to the embossing features of each secondplate.
 2. The method of claim 1 wherein the stamper plates include twoof the first plates and two of the second plates.
 3. The method of claim2 wherein the assembling is performed such that the first plates arepositioned adjacent to each other and the second plates are positionedadjacent to each other.
 4. The method of claim 2 wherein each firstplate is made using a single master template.
 5. The method of claim 4wherein each first plate is made from one or more intermediate replicasmade from the master template.
 6. The method of claim 4 wherein eachsecond plate is made from one of the first plates or an additional firstplate made using the master template.
 7. The method of claim 2 whereinthe embossing features of each plate include an identifier at each endof each plate, and wherein the identifiers of adjacent ends of adjacentplates are usable to identify each plate.
 8. The method of claim 1wherein the assembling comprises welding one of the at least one firstplate to one of the at least one second plate.
 9. The method of claim 1wherein the assembling comprises coupling together the multiple stamperplates to form a cylindrical body.
 10. The method of claim 1 wherein thestamper plates are formed with wobble patterns, and the wobble patternof each first stamper plate is vertically mirrored with respect to thewobble pattern of each second stamper plate.
 11. An embossing drum forembossing tape media, the embossing drum comprising: a first stamperplate for embossing the tape media; and a second stamper platepositioned proximate the first stamper plate for embossing the tapemedia, wherein the stamper plates have inverse land and groove patterns.12. The embossing drum of claim 11 wherein the land and groove patternscomprise wobble patterns, and the wobble pattern of the first stamperplate is vertically mirrored with respect to the wobble pattern of thesecond stamper plate.
 13. The embossing drum of claim 11 furthercomprising an additional first stamper plate having the sameconfiguration as the first stamper plate, and an additional secondstamper plate having the same configuration as the second stamper plate,wherein the stamper plates are attached together.
 14. The embossing drumof claim 13 wherein the first stamper plates are positioned adjacent toeach other, and the second stamper plates are positioned adjacent toeach other.
 15. The embossing drum of claim 13 wherein the land andgroove patterns comprise wobble patterns, and the wobble pattern of eachfirst stamper plate is vertically mirrored with respect to the wobblepattern of each second stamper plate.
 16. The embossing drum of claim 13wherein the land and groove patterns define embossing features, and theembossing features of each plate include an identifier at each end ofeach plate, and wherein the identifiers of adjacent ends of adjacentplates are usable to identify each plate.
 17. The embossing drum ofclaim 13 wherein the first stamper plates are made using a mastertemplate, and each second stamper plate is made from one of the firststamper plates or another first plate made from the master template. 18.The embossing drum of claim 11 wherein the first stamper plate is madeusing a master template.
 19. The embossing drum of claim 18 wherein thefirst stamper plate is made from one or more intermediate replicas madefrom the master template.
 20. The embossing drum of claim 18 wherein thesecond plate is made from the first plate or an additional first platemade using the master template.